Host memory exhaustion leading to VM kernel panic?

[jonc]

I need some help figuring out how Proxmox uses memory. I have an OVH server with a mere 8GB of RAM. Proxmox reports that it can see 7.70GB and that only 6.18GB is actually in use. I assume that Proxmox itself requires about 300MB of memory to run and reports only the amount of memory available for VM's to use as the Total figure we see below.

When I create a new Linux VM on this host and give it a range of memory say 384 - 512MB the VM runs fine. If I increase that memory to say 512 - 768MB I get VM kernel panics due to lack of memory. Thing is I have over 1GB of free memory, at least according to Proxmox. I'm obviously incorrectly interpreting how Proxmox is using the physical RAM available. Can anybody point me to some information on this so that I can enrich my mind on this matter?

Thanks!

 

[jonc]

*bump*

 

[mir]

How much RAM is reserved in BIOS for shared memory to graphics controller ?

 

[jonc]

That's a good question, I'd need to find out from OVH as I don't have access to the BIOS. You'd think this being a dedicated server that it wouldn't have a lot of shared memory for graphics functions.

 

[mir]

Just a guess looking at your stats could indicate that 256MB is reserved for shared memory to graphics since since 'Total RAM' shown is all available memory including memory for proxmox itself.

From one of my servers where I have configured the lowest possible reserved memory for graphics which is 32MB out of a total of 16GB.